1. Field of the Invention
The present invention relates to a sheet feeding device and an image forming apparatus.
2. Description of the Related Art
Various types of image forming apparatuses, such as a copier, a printer, a facsimile machine, and a multifunction peripheral that combines a copier, a printer and/or a facsimile machine, include a paper feeding device that takes out one paper sheet at a time from paper sheets stored in a paper sheet storage unit and feeds the paper sheet to an image forming unit.
Used in such various types of image forming apparatuses are various types of paper sheets other than plain paper, for example, coated paper, art paper, and film paper.
However, because such various types of paper sheets other than plain paper have a smooth sheet surface, have low air permeability, and are hygroscopic, such paper sheets tend to tightly adhere to each other. For this reason, these types of paper sheets have a problem in that, compared to plain paper sheets, they are not easily separated from each other and thus multiple paper sheets tend to be fed collectively and paper sheets tend not to be properly fed.
There are paper feeding devices that solve the above-described problem. In such paper feeding devices, side fences that regulate the side end positions of paper sheets are provided with side air nozzles and, by blowing the air supplied from an air supply unit, such as a blower, arranged in the side fences against the side end surfaces of stacked paper sheets, the paper sheets can be separated as they are fed (see Japanese Patent No. 4095656, Japanese Laid-open Patent Publication No. 2005-096893, Japanese Laid-open Patent Publication No. 2007-223700, and Japanese Laid-open Patent Publication No. 2006-327716).
There is another paper feeding device in which the side fences are not provided with air nozzles but the direction in which air is blown can be changed by rotating air nozzles and fans together (see Japanese Laid-open Patent Publication No. H02-144338). In this case, the air can be blown against the side end surfaces of the paper sheets at a desired angle.
However, the configuration for rotating the air nozzles and the fans together makes it difficult to house the air nozzles in the side fences because space allowing for the rotation is necessary, which increases the size of the device. Furthermore, there is also a problem in that the rotation mechanism for rotating the fans becomes complicated.
Therefore, there is a need for a sheet feeding device and an image forming apparatus, capable of changing the direction in which air is blown against paper sheets using a simple and compact configuration.